THE WESTERN AND CENTRAL PACIFIC TUNA FISHERY:

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3 THE WESTERN AND CENTRAL PACIFIC TUNA FISHERY: 2013 OVERVIEW AND STATUS OF STOCKS Shelton Harley, Peter Williams, Simon Nicol and John Hampton Secretariat of the Pacific Community Oceanic Fisheries Programme Tuna Fisheries Assessment Report No. 14 1

4 Copyright Secretariat of the Pacific Community (SPC), 2015 All rights for commercial/for profit reproduction or translation, in any form, reserved. SPC authorises the partial reproduction or translation of this material for scientific, educational or research purposes, provided that SPC and the source document are properly acknowledged. Permission to reproduce the document and/or translate in whole, in any form, whether for commercial/for profit or nonprofit purposes, must be requested in writing. Original SPC artwork may not be altered or separately published without permission. Original text: English Harley, S. J. Secretariat of the Pacific Community Cataloguing-in-publication data The western and central Pacific tuna fishery: 2013 overview and status of stocks / Shelton Harley, Peter Williams, Simon Nicol and John Hampton (Tuna Fisheries Assessment Report, no. 14 / Secretariat of the Pacific Community) ISSN: Tuna fisheries Pacific Ocean. 2. Tuna populations Pacific Ocean. I. Harley, S. J. II. Williams, Peter Gordon III. Nicol, Simon IV. Hampton, John V. Title VI. Secretariat of the Pacific Community VII. Series AACR2 ISBN: ISSN: Acknowledgements: We are grateful to the member countries of the Pacific Community and the fishing nations involved in the western and central Pacific tuna fishery for their cooperation in the provision of fishery data used in this report. Regional fisheries research and monitoring carried out by the Oceanic Fisheries Programme are currently funded by numerous sources, including the Australian Agency for International Development (AusAID), the New Zealand Aid Programme, the Government of France, and the European Community project, Scientific Support for the Management of Coastal and Oceanic Fisheries (SciCOFish). Prepared for publication and printed at the Secretariat of the Pacific Community Noumea, New Caledonia,

5 Contents Preface 4 1 The western and central Pacific tuna fishery 1 2 Status of tuna stocks Skipjack tuna Yellowfin tuna Bigeye tuna South Pacific albacore tuna 6 3 Ecosystem considerations Catch composition Impact of catches Tuna tagging 8 Figures 9 For further information 24 Tables 26 3

6 Preface Tuna fisheries assessment reports provide current information on the tuna fisheries of the western and central Pacific Ocean and the fish stocks (mainly tuna) that are impacted by them. The information provided in this report is summary in nature, but a list of references (mostly accessible via the Internet) is included for those seeking further details. This report focuses on the main tuna stocks targeted by the fishery skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), bigeye tuna (T. obesus), and South Pacific albacore tuna (T. alalunga). The report is in three main parts: the first section provides an overview of the fishery, with emphasis on developments over the past few years; the second summarises the most recent information on the status of the stocks; and the third summarises information concerning the interaction between the tuna fisheries and other associated and dependent species. The data used in compiling the report are those which were available to the Oceanic Fisheries Programme (OFP) at the time of publication, and are subject to change as improvements continue to be made to recent and historical catch statistics from the region. The fisheries statistics presented will usually be complete to the end of the year prior to publication. However, some minor revisions to statistics may be made for recent years from time to time. The stock assessment information presented is the most recent available at the time of publication. Inquiries regarding this report or other aspects of the work programme of the OFP should be directed to: Oceanic Fisheries Programme Manager Secretariat of the Pacific Community BP D Noumea Cedex New Caledonia For further information, including a complete online French version of this report, see the OFP webpage: 4

7 1 The western and central Pacific tuna fishery The tuna fishery in the western and central Pacific Ocean (WCPO), encompassed by the Convention Area of the Western and Central Pacific Fisheries Commission (WCP CA) (Figure 1), is a diverse fishery, ranging from small-scale, artisanal operations in the coastal waters of Pacific states, to large-scale, industrial purse-seine, pole-and-line and longline operations in the exclusive economic zones (EEZs) of Pacific states and in international waters (high seas). The main species targeted by these fisheries are skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), bigeye tuna (T. obesus) and albacore tuna (T. alalunga). The current fishery characterisation includes updates to historical data, which are greatest for 2012, particularly the gear-specific breakdown of catches from Indonesia. We expect revisions to the 2013 catch estimates for these fleets in next year s report, particularly catch estimates relating to the troll gear which were very high for the tropical tunas. Annual total catches of the four main tuna species (skipjack, yellowfin, bigeye and albacore) in the WCP CA increased steadily during the 1980s as the purse-seine fleet expanded, and remained relatively stable during most of the 1990s until the sharp increase in catch in Over the past seven years there has been an upward trend in total tuna catch, primarily due to increases in purse-seine fishery catches (Figure 2 and Table 2). The provisional total WCP CA tuna catch for 2013 was estimated at 2,627,696 tonnes (t) a small drop from the record high of 2,662,538 t experienced in 2012, and the second-highest catch on record. In 2013 the purse-seine fishery accounted for an estimated 1,899,015 t (72% of the total catch, and the highest-ever catch for this fishery, eclipsing the previous record catch in 2012), with pole-andline taking an estimated 221,715 t (8% the lowest catch in over 40 years). The longline fishery in 2013 accounted for an estimated 230,137 t (9% the lowest catch this century), and the remainder (10%) was taken by troll gear and a variety of artisanal gear, mostly in eastern Indonesia, the Philippines, and Vietnam. The WCP CA tuna catch for 2013 represented 82% of the total Pacific Ocean catch and 58% of the global tuna catch (the provisional estimate for 2013 is 4,517,435 t). The 2013 WCP CA catch of skipjack (1,810,166 t 69% of the total catch) was the highest recorded catch, eclipsing the previous record from 2009, and a 2% increase over the 2012 catch (Table 2). The WCP CA yellowfin catch for 2013 (524,022 t 20%) was slightly below the average of the past 10 years. The highest on record estimate for 2012, of 646,165 t, provided in last year s report, was revised down to 587,192 t after further consideration of catch estimates from Indonesia. The WCP CA bigeye catch for 2013 (150,281 t 6%) is around the average of the proceeding nine years, and is a 7% decrease from the 2012 catch, driven by a reduction in longline catches to the lowest level since The 2013 WCP CA albacore catch (143,227 t 5%) was the second-highest on record, with small longline catches from the South Pacific stock offset by increases in catches in the North Pacific. The 2012 purse-seine catch of 1,899,015 t was the second-successive record catch for this fishery (Figure 3 and Table 1). The 2013 purse-seine skipjack catch (1,476,855 t 82% of the total skipjack catch) was a 5% increase from the 2012 catch and the highest on record. The 2013 purse-seine catch of yellowfin tuna (344,141 t) was a 5% decrease from The purse-seine catch estimate for bigeye tuna for 2013 (73,826 t) was the highest on record, and 15% higher than 2012, and represented 49% of the total 2013 bigeye catch. This would represent the first year in which the purse-seine catch of bigeye tuna exceeded the longline catch. However, it is important to note that the purse-seine species composition for 2013 will be revised once all observer data for 2013 have been received and processed, and the current estimate should therefore be viewed as preliminary. 1

8 The 2013 longline catch of 230,137 t was the lowest since 1999, and a 13% decrease from 2012 (Figure 4 and Table 1). The reason for this is not yet clear, and longline catch estimates are often uncertain and subject to revision. Nevertheless, the bigeye (62,587 t) and yellowfin (65,492 t) catches for 2013 were both the lowest in over 20 years. The 2013 pole-and-line catch of 221,715 t was the lowest catch in over 40 years, and represented a 9% decrease on the 2012 catch (Figure 5 and Table 1). Skipjack tends to account for the majority of the catch (approximately 70 80% in recent years, but typically more than 85% of the total catch in tropical areas), and albacore (8 20% in recent years) is taken by the Japanese coastal and offshore fleets in the temperate waters of the northern Pacific Ocean. Yellowfin tuna (5 10%), and a small component of bigeye tuna (1 6%), made up the remainder of the catch. The Japanese distant-water and offshore fleet, and the Indonesian fleet, account for most of the WCP CA pole-and-line catch. The 2013 troll albacore catch in the South Pacific of 3,226 t was 8% higher than the 2012 catch, and the highest since Since 2008 only New Zealand (averaging 2,500 t per year) and the United States (averaging 260 t per year) have had vessels operating in the troll fishery. 2 Status of tuna stocks The sections below provide a summary of the recent developments in fisheries for each species, and the results from the most recent stock assessments. A summary of the important biological reference points for the four stocks is provided in Table 3. The three tropical tunas were assessed in 2014, while South Pacific albacore was last assessed in Due to uncertainty in the data for 2013, the three tropical tuna assessments only used fisheries data through to Information on the status of other oceanic fisheries resources (e.g., billfishes and sharks) is provided in the section on Ecosystem considerations. 2.1 Skipjack tuna The 2013 WCP CA skipjack catch of 1,810,166 t was the highest on record, although it was only 2% higher than the 2012 catch (Figure 6 and Table 4). As has been the case in recent years, the main contributor to the overall catch of skipjack was catch taken in the purse-seine fishery (1,476,855 t in % of total skipjack catch). The next-highest proportion of the catch was pole-and-line gear (161,220 t 9%). The longline fishery accounted for less than 1% of the total catch. The vast majority of the skipjack catch is taken in equatorial areas, and most of the remainder is taken in the seasonal home-water fishery of Japan (Figure 6). The dominant mode of the WCP CA skipjack catch (by weight) typically falls in the size range between 40 cm and 60 cm, corresponding to 1 2+ year-old fish (Figure 6). For pole-and-line the fish typically range between 40 cm and 55 cm, while for the domestic fisheries of Indonesia and the Philippines they are much smaller (20 40 cm). It is typically found that skipjack taken in unassociated (free-swimming) schools are larger than those taken in associated schools. 2

9 2.1.1 Stock assessment The most recent assessment of skipjack in the WCPO was conducted in 2014, and included data from 1972 to While estimates of fishing mortality for skipjack have increased over time, current fishing mortality rates for skipjack tuna are estimated to be about 0.62 times the level of fishing mortality associated with maximum sustainable yield (F MSY ). Therefore, overfishing is not occurring (i.e. F CURRENT < F MSY ) (Figure 7). Estimated recruitment shows an upward trend over time, but estimated biomass is declining over time, to about 52% of the level predicted in the absence of fishing. Nevertheless, recent spawning biomass levels are estimated to be well above the SB MSY level and the recently adopted limit reference point of 20% of the level predicted in the absence of fishing. The conclusions of the Western and Central Pacific Fisheries Commission (WCPFC) Scientific Committee at its 10th Regular Session (SC10), which were presented as recommendations to the Commission, are reproduced below (emphasis added): Recent catches are slightly above the estimated MSY of 1,532,000 mt. The assessment continues to show that the stock is currently only moderately exploited (F current /F MSY = 0.62) and fishing mortality levels are sustainable. However, the continuing increase in fishing mortality and decline in stock size are recognized. SC10 advised the WCPFC that there is concern that high catches in the equatorial region could result in range contractions of the stocks, thus reducing skipjack availability to high latitude fisheries. Fishing is having a significant impact on stock size, especially in the western equatorial region and can be expected to affect catch rates. The stock distribution is also influenced by changes in oceanographic conditions associated with El Niño and La Niña events, which impact on catch rates and stock size. Additional purse-seine effort will yield only modest gains in long-term skipjack catches and may result in a corresponding increase in fishing mortality for bigeye and yellowfin tunas. The management of total effort in the WCPO should recognize this. The spawning biomass is now around the mid-point of the range of candidate TRPs of 40%, 50%, and 60% of unfished spawning stock biomass that WCPFC10 has asked the SC10 to consider for skipjack. SC10 recommends the commission take action to avoid further increases in fishing mortality and keep the skipjack stock around the current levels, with tighter purse-seine control rules and advocates for the adoption of TRP and harvest control rules. 2.2 Yellowfin tuna The WCPC-CA yellowfin catch in 2013, of 524,022 t, was an 11% decrease from the 2012 catch (Figure 8 and Table 5). Purse-seine catches (344,141 t) declined by 5%, and longline catches (65,492 t) declined by 18%, from 2012 levels, and the longline catch was the lowest in over 20 years. The remainder of the yellowfin tuna catch comes from pole-and-line and troll, and the domestic fisheries in Indonesia, Vietnam and the Philippines. The purse-seine catch of yellowfin tuna is typically around four times the size of the longline catch. As with skipjack, the great majority of the yellowfin catch is taken in equatorial areas by large purse-seine vessels, and a variety of gear in the Indonesian and Philippine fisheries. The domestic surface fisheries of 3

10 the Philippines and Indonesia take large numbers of small yellowfin in the range cm. In the purseseine fishery, greater numbers of smaller yellowfin are caught in log and fish aggregation device (FAD) sets than in unassociated sets. A major proportion (by weight) of the purse-seine catch is adult (> 100 cm) yellowfin tuna; the purse-seine catch (by weight) of adult yellowfin tuna is usually higher than the longline catch, which was the case in 2008, where exceptional catches of large yellowfin in the size range cm were experienced in the purse-seine fishery Stock assessment The most recent assessment of yellowfin tuna in the WCPO was conducted in 2014 and included data from 1952 to Fishing mortality has increased in recent years. Current fishing mortality rates for yellowfin tuna are estimated to be about 0.72 times the level of fishing mortality associated with maximum sustainable yield (F MSY ), which indicates that overfishing is not occurring (Figure 9). However, recent catches are close to or exceed the MSY by up to 13%. Both biomass and recruitment have declined gradually over the duration of the fishery, with current spawning biomass estimated to be about 38% of the level predicted in the absence of fishing. Nevertheless, recent spawning biomass levels are estimated to be well above the SB MSY level and the recently adopted limit reference point of 20% of the level predicted in the absence of fishing. The conclusions of the WCPFC Scientific Committee at its 10th Regular Session (SC10), which were presented as recommendations to the Commission, are reproduced below (emphasis added): The WCPO yellowfin spawning biomass is above the biomass-based LRP WCPFC adopted, 0.2SBF=0, and overall fishing mortality appears to be below F MSY. It is highly likely that stock is not experiencing overfishing and is not in an overfished state. Latest (2012) catches (612,797mt (SC10-GW-WP-01)) of WCPO yellowfin tuna marginally exceed the MSY (586,400mt). The SC also noted that levels of fishing mortality and depletion differ between regions, and that fishery impact was highest in the tropical region (regions 3, 4, 7, 8 in the stock assessment model). The WCPFC could consider measures to reduce fishing mortality from fisheries that take juveniles, with the goal to increase to maximum fishery yields and reduce any further impacts on the spawning potential for this stock in the tropical regions. WCPFC could consider a spatial management approach in reducing fishing mortality for yellowfin. The SC recommend that the catch of WCPO yellowfin should not be increased from 2012 levels which exceeded MSY and measures should be implemented to maintain current spawning biomass levels until the Commission can agree an appropriate TRP. 4

11 2.3 Bigeye tuna The 2013 WCP CA bigeye tuna catch was 150,281 t, which was 7% lower than the 2012 catch, although a large (22%) decrease in longline catches was partially offset by a record purse-seine catch of 73,826 t, which was 15% higher than the 2012 catch (Figure 10 and Table 6). Purse-seine catches comprised 49% of the total catch, longline was 41% of the catch, and the remainder was distributed across troll, pole and line, and other gears. This would represent the first year in which the purse-seine catch of bigeye tuna exceeded the longline catch, but it is important to note that the purse-seine species composition for 2013 will be revised once all observer data for 2013 have been received and processed, and the current estimate should therefore be viewed as preliminary. The majority of the WCP CA catch is taken in equatorial areas, by both purse-seine and longline, but with some longline catch in sub-tropical areas (e.g. east of Japan and off the east coast of Australia). In the equatorial areas much of the longline catch is taken in the central Pacific, contiguous with the important traditional bigeye longline area in the eastern Pacific. As with skipjack and yellowfin tuna, the domestic surface fisheries of the Philippines and Indonesia take large numbers of small bigeye in the range cm. The longline fishery clearly accounts for most of the catch (by weight) of large bigeye in the WCP CA. This contrasts with large yellowfin tuna, which (in addition to the longline gear) are also taken in significant amounts from unassociated schools in the purse-seine fishery and in the Philippines handline fishery. Large bigeye are very rarely taken in the WCPO purse-seine fishery, and only a relatively small amount comes from the handline fishery in the Philippines. Bigeye sampled in the longline fishery are predominantly adult fish with a mean size of approximately 130 cm (range cm) Stock assessment The most recent assessment of bigeye tuna in the WCPO was conducted in 2014, and this included data from 1952 to Fishing mortality is estimated to have increased over time, particularly in recent years, and current levels are 1.57 times the F MSY level (F CURRENT > F MSY ). Therefore, overfishing is occurring (Figure 11). The biomass of spawners is estimated to have declined over the duration of the fishery, with current spawning biomass estimated to be about 16% of the level predicted in the absence of fishing. Recent spawning biomass levels are estimated to be below both the SB MSY level and the recently adopted limit reference point of 20% of the level predicted in the absence of fishing. The conclusions of the WCPFC Scientific Committee at its 10th Regular Session (SC10), which were presented as recommendations to the Commission, are reproduced below (emphasis added): SC10 noted that the spawning biomass of WCPO bigeye tuna breached the biomass LRP in 2012 and that the stock was overfished. Rebuilding spawning biomass to be above the biomass LRP will require a reduction in fishing mortality. SC10 recommended that fishing mortality on WCPO bigeye tuna be reduced. A 36% reduction in fishing mortality from the average levels for would be expected to return the fishing mortality rate to FMSY. This reduction of at least 36% should also allow the stock to rebuild above 5

12 the LRP over a period of time. This recommended level of reduction in fishing mortality could also be stated as a minimum 33% reduction from the 2004 level of fishing mortality, or a minimum 26% reduction from the average level of fishing mortality. Overfishing and the increase in juvenile bigeye catches have resulted in a considerable reduction in the potential yield of the WCPO bigeye stock. The loss in yield per recruit due to excess harvest of juvenile fish is substantial. SC10 concluded that MSY levels would increase if the mortality of juvenile bigeye was reduced. Fishing mortality varies spatially within the Convention Area with high mortality in the tropical Pacific Ocean. WCPFC could consider a spatial management approach in reducing fishing mortality for bigeye tuna. 2.4 South Pacific albacore tuna The South Pacific albacore catch in 2013 (84,835 t) represented a slight decrease (3%) from 2012, despite the increasing numbers of vessels in the fishery (Figure 12 and Table 7). Longline fishing has accounted for most of the catch of this stock (> 75% in the 1990s, but > 90% in recent years). The troll catch, covering a season spanning November to April, has generally been in the range of 3,000 8,000 t, however it has averaged around 2,700 t over the past five years. The longline catch is widely distributed in the South Pacific, but with catches concentrated in the western part of the Pacific. Much of the increase in catches is attributed to catches taken by Chinese-Taipei and Chinese vessels fishing north of latitude 20 S. The Pacific Island domestic longline fleet catch is restricted to latitudes S. Troll catches are distributed in New Zealand s coastal waters, mainly off the South Island, and along the sub-tropical convergence zone (STCZ). Usually, less than 20% of the overall South Pacific albacore catch is taken east of 150 W. The longline fishery takes adult albacore, mostly in the narrow size range of cm, and the troll fishery takes juvenile fish in the range cm. Juvenile albacore also occasionally appear in the longline catch Stock assessment The most recent stock assessment for South Pacific albacore tuna was undertaken in 2012, and was based on data from 1960 to For this assessment a single model run (a reference case) was chosen to show trends in stock size, but the WCPFC Scientific Committee reached conclusions regarding stock status, sustainable yields and subsequent management advice based on the median outcomes from a large number of model runs. The assessment indicates that fishing mortality on adult fish has increased considerably over the past decade, but that overall estimates of fishing mortality are well below F MSY. This indicates that overfishing is not occurring (Figure 13). Spawning biomass levels remain well above SB MSY, so the stock is not in an overfished state. Nevertheless, it is estimated that the current level of longline catch is having a considerably higher impact on the stock that is vulnerable to the longline fishery. The assessment indicates that the current level of impact is about 70% of that for fish of the size ranges taken in the northern longline fisheries, and this has increased sharply in recent years. 6

13 Given the recent expansion of the fishery and recent declines in exploitable biomass available to longline fisheries, and given the importance of maintaining catch rates, the WCPFC Scientific Committee recommended that longline fishing mortality be reduced if the Commission wishes to maintain economically viable catch rates. 3 Ecosystem considerations The Convention on the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean identified ecosystem issues as an important element in the principles for conservation and management of the tuna resource in the WCP CA. This section of the report provides a brief summary of the information available from the WCP CA tuna fishery concerning associated and dependent species, including information about the species composition of the catch from the tuna fisheries and an assessment of the impact of the fishery on these species. It is important to note that most of these species have received limited attention to date and, consequently, it is only possible to provide an assessment of the impact of the fishery for a limited range of species. This section also includes a summary review of recent research and research that is currently being undertaken to learn more about the relationship between the main tuna species and the pelagic ecosystem. 3.1 Catch composition The tuna fisheries of the WCPO principally target four main tuna species: skipjack, yellowfin, bigeye and albacore tuna. However, the fisheries also catch a range of other species in association with these. Some of the associated species are of commercial value (by-products), while many others are discarded. There are also incidents of the capture of species of ecological and/or social significance ( protected species ), including marine mammals, sea turtles and some species of shark (e.g. whale sharks). The information concerning the catch composition of the main tuna fisheries in the WCPO comes largely from the various observer programmes operating in the region. Overall, catch (in weight) from unassociated and associated purse-seine sets are dominated by tuna species (99.6% and 98.5%, respectively), with anchored FAD sets having the lowest tuna catch weight (99%). There is limited interaction with protected species, such as whale sharks and manta rays (Figure 14). Historically, some vessels deliberately set around whale sharks associated with tuna schools, but this practice has been banned. In a very small percentage of cases of free schools sets a whale shark is encountered despite not being observed before the set was made. Species composition of the catch has also been estimated for three main longline fisheries operating in the WCPO: the western tropical Pacific (WTP) shallow-setting longline fishery, the WTP deep-setting longline fishery, and the western South Pacific (WSP) albacore fishery. While estimates are uncertain due to the low level of observer coverage, some general conclusions are possible. The main tuna species account for 46%, 74% and 71% of the total catch (by weight) of the three fisheries, respectively (Figure 14). The WTP shallow fishery has a higher proportion of non-tuna species in the catch, principally shark and billfish species, while mahi mahi and opah (moonfish) represent a significant component of the WSP albacore longline catch. There are also considerable differences in the species composition of the billfish catch in the three fisheries, while, overall, the WTP shallow and WSP albacore fisheries catch a higher proportion of surface-orientated species than does the WTP deep-setting fishery. 7

14 Interactions with seabirds and marine mammals were very low in all three longline fisheries. Catches of five species of marine turtles were observed in the equatorial longline fishery, although the observed encounter rate was very low, and most of the turtles caught were alive at the time of release. The recent WCPFC ban on the use of shark lines should reduce the catch of silky and oceanic whitetip sharks; the status of these two species is of current concern. 3.2 Impact of catches In addition to the main tuna species, annual catch estimates for the WCPO in 2013 are available for the main species of billfish (swordfish [20,043 t], blue marlin [19,524 t], striped marlin [3,678 t] and black marlin [2,340 t]). For all of these species other than striped marlin, current catches are around the average for the past decade. However, for striped marlin, the 2013 catch estimate represents the lowest since records began. Catches of other associated species cannot be accurately quantified using logsheet data, but estimates should be possible as longline observer coverage increases. Purse-seine observer coverage is already sufficiently high to estimate catches of associated species. Over the past several years stock assessments have been made for several billfish and shark species in addition to the main tuna species. Table 8, summarises the recommendations from the WCPFC Scientific Committee to the Commission. 3.3 Tuna tagging Large-scale tagging experiments are required to provide the level of information (fishery exploitation rates and population size) that is necessary to enable tuna stock assessments of tropical tunas in the western and central Pacific Ocean. Tagging data have the potential to provide significant information of relevance to stock assessment, either by way of stand-alone analyses or, preferably, through their integration with other data directly in the stock assessment model. Tuna tagging has been a core activity of the Oceanic Fisheries Programme over the last 30 years, with tagging campaigns occurring in the 1970s, 1990s and, most recently, since This most recent campaign has now tagged and released over 400,000 tuna in the equatorial western and central Pacific Ocean, with over 70,000 reported recaptures (Figure 15 and Table 9). 8

15 Figure 1: The western and central Pacific Ocean (WCPO), the eastern Pacific Ocean (EPO) and the WCPFC Convention Area boundary. Note: WCP CA in dashed lines. 9

16 Figure 2: Catch (metric tonnes) by gear (top) and species (bottom) for the western and central Pacific region, Note: data for 2013 are preliminary. 10

17 Figure 3: Time series of catch (t) (top), recent spatial distribution of catches (middle), and fleet sizes (bottom) for the purseseine fishery in the western and central Pacific Ocean (WCPO). 11

18 12 Figure 4: Time series of catch (t) (top), recent spatial distribution of catches (middle), and fleet sizes (bottom), for the longline fishery in the western and central Pacific Ocean (WCPO).

19 Figure 5: Time series of catch (t) (top), recent spatial distribution of catches (middle), and fleet sizes (bottom), for the pole-and-line fishery in the western and central Pacific Ocean (WCPO). 13

20 14 Figure 6: Time series (top), recent spatial distribution (middle), and size composition (average for last five years; bottom) of skipjack tuna catches (t) by gear for the western and central Pacific Ocean (WCPO).

21 Figure 7: Estimated recruitment (top left), spawning biomass (top right), fishing mortality (middle left), stock status (middle right) and estimated spawning biomass with [blue] and without [red] fishing (bottom left) from the 2014 skipjack tuna stock assessment. 15

22 16 Figure 8: Time series (top), recent spatial distribution (middle), and size composition (average for last five years, bottom) of yellowfin tuna catches (t) by gear for the western and central Pacific Ocean (WCPO).

23 Figure 9: Estimated recruitment (top left), spawning biomass (top right), fishing mortality (middle left), stock status (middle right), estimated spawning biomass with [blue] and without [red] fishing (bottom left), and spawning biomass for the western equatorial region (bottom right) from the 2014 yellowfin tuna stock assessment. 17

24 Figure 10: Time series (top), recent spatial distribution (middle), and size composition (average for last five years; bottom) of bigeye tuna catches (t) by gear for the western and central Pacific Ocean (WCPO). 18

25 Figure 11: Estimated recruitment (top left), spawning biomass (top right), fishing mortality (middle left), stock status (middle right), and estimated spawning biomass with [blue] and without [red] fishing (bottom left) from the 2014 bigeye tuna stock assessment. 19

26 Figure 12: Time series (top), recent spatial distribution (middle), and size composition (average for last five years, bottom) of South Pacific albacore tuna catches (t) by gear for the western and central Pacific Ocean (WCPO). 20

27 Figure 13: Estimated recruitment (top left), spawning biomass (top right), fishing mortality (middle left), stock status (middle right), and estimated spawning biomass with [blue] and without [red] fishing (bottom left) from the 2012 South Pacific albacore tuna stock assessment. 21

28 22 Figure 14: Catch composition of the various categories of purse-seine (top) and longline (bottom) fisheries operating in the WCPO based on observer data based on the last 10 years data.

29 Figure 15: Tag releases (top) and recaptures (bottom) by species from the recent Pacific Tuna Tagging Programme (PTTP). 23

30 For further information 1 Fishery Lawson T Comparison of the species composition of purse-seine catches determined from logsheets, observer data, market data, cannery receipts and port sampling data/supplementary information. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC10-ST-WP-01. Williams P Estimates of annual catches in the WCPFC Statistical Area (Rev.1 23 July 2014). Noumea, New Caledonia: Secretariat of the Pacific Community.WCPFC-SC10-ST-IP-01. Williams P. and P. Terawasi Overview of tuna fisheries in the western and central Pacific Ocean, including economic conditions Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC10-GN-WP-01. Status of the stocks Davies N., et al Stock assessment of striped marlin (Kajikia audux) in the southwest Pacific Ocean. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC8-SA-WP-05. Davies N., et al Stock assessment of swordfish (Xiphias gladius) in the southwest Pacific Ocean. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC9-SA-WP-05. Davies N. S. Harley, J. Hampton and S. McKechnie Stock assessment of yellowfin tuna in the western and central Pacific Ocean Rev 1 (25 July 2014). Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC10- SA-WP-04. Harley S., N. Davies, J. Hampton and S. McKechnie Stock assessment of bigeye tuna in the western and central Pacific Ocean Rev 1 (25 July 2014). Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC10-SA-WP-01. Hoyle S., et al Stock assessment of albacore tuna in the South Pacific Ocean. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC8-SA-WP-04. Rice J., and S. Harley Stock assessment of oceanic whitetip sharks in the western and central Pacific Ocean. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC8-SA-WP-06. Rice J., and S. Harley Updated stock assessment of silky sharks in the western and central Pacific Ocean. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC9-SA-WP-03. Rice J. et al Stock assessment of skipjack tuna in the western and central Pacific Ocean. (Rev 1 25 July 2014). Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC10- SA-WP-05. Rice J., et al Stock assessment of blue shark in the North Pacific Ocean using stock synthesis. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC10- SA-WP-08. Ecosystem considerations Allain V Trophic structure of the pelagic ecosystems of the western and central Pacific Ocean. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC6-EB-IP All WCPFC documents can be obtained by visiting the WCPFC website ( and navigating to the meeting where the document was presented, e.g. WCPFC-SC6-GN-WP-1 can be found on the webpage of documents presented to the 6 th session of the Scientific Committee. ( 24

31 Allain V., et al WCPO ecosystem indicator trends and results from ECOPATH simulations. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC8-EB-IP-11. Allain V., et al Interaction between Coastal and Oceanic Ecosystems of the western and central Pacific Ocean through predator-prey relationship studies. PLoS ONE. 7(5): e Bromhead D., et al Ocean acidification impacts on tropical tuna populations. Deep Sea Research II. Caneco B. et al Analysis of WCPO longline observer data to determine factors impacting catchability and condition on retrieval of oceanic whitetip, silky, blue, and thresher sharks. St Andrews, Scotland: DMP Statistics. WCPFC SC10 EB WP 01. Evans K., et al Progressing adaptation to climate variability and change in western and central Pacific Ocean tuna fisheries. Hobart, Australia: Commonwealth Scientific and Industrial Research Organisation (CSIRO). WCPFC-SC8-EB-WP-01. Farley J.H., et al Reproductive dynamics and potential annual fecundity of South Pacific albacore tuna (Thunnus alalunga). PLoS ONE 8(4): e doi: /journal.pone Fitzsimmons L., and S. Bunce Bycatch mitigation information system (BMIS). Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC9-EB-IP-03. Harley S. J., and Williams, P Spatial and temporal distribution of whale sharks in the WCPO based on observer data and other data sources. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC9-EB-WP-01. Lehodey P., et al Project 62: SEAPODYM applications in WCPO. WCPFC-SC EB-WP-02. Leroy B., et al A critique of the ecosystem impacts of drifting and anchored FADs use by purseseine tuna fisheries in the western and central Pacific Ocean. Aquatic Living Resources. DOI / alr/ OFP Non-target species interactions with the tuna fisheries of the western and central Pacific Ocean. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC6-EB-IP-08. OFP Summary Information on whale shark and cetacean interactions in the tropical WCPFC purseseine fishery. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC8-2012/ SC8- WCPFC8-04. OFP A report on the activities completed for shark research plan by the SPC OFP. Noumea, New Caledonia: Secretariat of the Pacific Community. WCPFC-SC10-EB-WP-04. Usu, T. et al Pacific Tuna Tagging and PNG Tagging Project Progress Report and Workplan for Rev 1 (25 July 2014). WCPFC-SC /RP-PTTP-02. Williams A.J., et al Spatial and sex-specific variation in growth of albacore tuna (Thunnus alalunga) across the South Pacific Ocean. PLoS ONE 7(6): e doi: /journal.pone

32 Table 1: Catch (metric tonnes) by gear for the western and central Pacific region, Year Longline Pole-and-line Purse seine Troll Other Total ,874 73,800 5, , , , ,070 14, , , , ,412 18, , , ,263 98,628 11, , , , ,323 29, , , , ,621 8, , , , ,900 16, , , , ,774 14, , , , ,954 15, , , , ,784 9, , , , ,754 16, , , , ,914 24, , , , ,745 29, , , , ,841 36, , , , ,499 29, , , , ,663 27, , , , ,627 40, , , , ,257 53, , , , ,482 52,040 1, , , , ,799 90, , , , , ,265 1,489 89, , , , ,907 2, , , , , ,233 2, , , , , , ,378 1,064, , , ,467 3, ,478 1,155, , , ,252 3, ,812 1,009, , , ,460 2, ,873 1,143, , , ,142 2, ,849 1,140, , , ,610 4, ,193 1,277, , , ,441 8, ,164 1,303, , , ,732 7, ,508 1,420, , , ,151 8, ,129 1,655, , , ,313 6, ,536 1,596, , , ,647 4, ,262 1,483, , , ,648 7, ,850 1,632, , , ,173 23, ,062 1,646, , , ,907 17, ,032 1,640, , , ,355 18, ,199 1,703, , ,645 1,297,726 19, ,779 2,105, , ,480 1,131,142 13, ,900 1,914, , ,854 1,168,428 25, ,670 1,997, , ,483 1,144,442 17, ,934 1,910, , ,202 1,297,473 16, ,317 2,096, , ,905 1,292,287 19, ,218 2,100, , ,179 1,393,992 23, ,314 2,284, , ,735 1,479,328 13, ,972 2,199, , ,594 1,512,945 10, ,599 2,239, , ,661 1,655,500 9, ,044 2,428, , ,551 1,709,351 11, ,565 2,478, , ,350 1,785,825 9, ,286 2,606, , ,123 1,703,134 11, ,010 2,503, , ,070 1,549,060 11, ,731 2,320, , ,958 1,840,529 14, ,976 2,662, , ,715 1,899,015 88, ,959 2,627,696 Note: data for 2013 are preliminary. 26

33 Table 2: Catch (metric tonnes) by species for the four main tuna species taken in the western and central Pacific region, Year Albacore tuna Bigeye tuna Skipjack tuna Yellowfin tuna Total ,463 45,025 89,938 73, , ,922 39, ,736 75, , ,602 36, ,624 83, , ,815 44, ,703 75, , ,687 32, ,918 74, , ,735 31, ,221 73, , ,284 33, ,514 93, , ,822 36, ,840 68, , ,213 30, ,031 81, , ,106 34, ,031 87, , ,350 40, ,398 99, , ,737 43, , , , ,655 57, , , , ,149 48, , , , ,162 52, , , , ,651 69, , , , ,947 82, , , , ,171 83, , , , ,161 66, , , , ,007 73, , , , ,156 72, , , , ,095 63, , , , ,496 71, , , , ,988 77, , ,234 1,064, ,540 85, , ,265 1,155, ,060 88, , ,423 1,009, ,757 93, , ,175 1,143, , , , ,463 1,140, , , , ,314 1,277, , , , ,916 1,303, , , , ,884 1,420, , ,414 1,063, ,175 1,655, , , , ,295 1,596, , , , ,008 1,483, , , , ,406 1,632, , ,763 1,028, ,433 1,646, , ,892 1,016, ,508 1,640, , , , ,335 1,703, , ,581 1,206, ,670 2,105, , ,189 1,099, ,775 1,914, , ,594 1,184, ,079 1,997, , ,661 1,109, ,722 1,910, , ,394 1,289, ,759 2,096, , ,598 1,288, ,792 2,100, , ,860 1,387, ,927 2,284, , ,908 1,403, ,095 2,199, , ,309 1,505, ,102 2,239, , ,920 1,658, ,348 2,428, , ,333 1,631, ,117 2,478, , ,163 1,792, ,602 2,606, , ,404 1,697, ,851 2,503, , ,014 1,543, ,373 2,320, , ,017 1,770, ,192 2,662, , ,281 1,810, ,022 2,627,696 Note: data for 2013 are preliminary. 27

34 Table 3: Biological reference points from the latest stock assessments for South Pacific albacore, bigeye, skipjack, and yellowfin tunas. Note: All biomasses are in metric tonnes (t). B is the average estimated unfished biomass; B 0 is the CURR average biomass over the last 3-4 years; MSY is the maximum sustainable yield based on recent patterns of fishing; F CURR / F MSY is the ratio of recent fishing mortality to that which will support the MSY; SB CURR /SB MSY is the ratio of recent spawning biomass to that which will support the MSY. S. Pacific albacore Bigeye Skipjack Yellowfin B0 1,131,000 2,228,600 6,281,000 4,319,000 B CURR 1,028, ,967 3,615,213 1,994,655 MSY 99, ,520 1,532, ,400 F CURR/ F MSY SB CURR/ SB MSY SB CURR/ SB F=

35 Table 4: Skipjack tuna catch (metric tonnes) by gear type for the western and central Pacific region, Year Longline Pole-and-line Purse seine Troll Other Total ,428 3, ,782 89, ,011 11, , , ,387 11, , , ,757 9, , , ,106 25, , , ,933 4, , , ,600 10, , , ,846 10, , , ,379 7, , , ,795 5, , , , ,074 7, , , , ,284 13, , , , ,827 18, , , , ,217 19, , , , ,202 10, , , , ,271 13, , , , ,582 22, , , , ,641 34, , , , ,401 33, , , , ,859 58, , , ,597 76, , , ,065 90, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,577 1,063, , , , , , , , , , , , , , ,609 12,298 78,343 1,028, , , ,781 6,514 99,235 1,016, , , ,504 9,218 86, , , , ,926 8, ,686 1,206, , , ,216 5, ,578 1,099, , , ,313 15, ,573 1,184, , , ,857 7, ,415 1,109, , , ,999 6, ,811 1,289, , , ,809 9, ,759 1,288, , , ,114 15, ,364 1,387, , ,715 1,055,434 6, ,769 1,403, , ,731 1,153,869 3, ,418 1,505, , ,010 1,278,316 3, ,190 1,658, ,570 1,237,748 4, ,763 1,631, , ,323 1,415,731 4, ,062 1,792, , ,409 1,309,387 4, ,803 1,697, , ,843 1,181,457 4, ,843 1,543, , ,538 1,409,507 6, ,082 1,770, , ,220 1,476,855 52, ,669 1,810,166 Note: data for 2013 are preliminary. 29

36 Table 5: Yellowfin tuna catch (metric tonnes) by gear type for the western and central Pacific region, Year Longline Pole-and-line Purse seine Troll Other Total ,020 1,872 1, ,337 73, ,166 3,259 2, ,236 75, ,547 4,225 6, ,197 83, ,185 2,071 2, ,223 75, ,247 5,074 3, ,186 74, ,493 3,434 3, ,956 73, ,654 2,192 5, ,409 93, ,083 3,125 3, ,303 68, ,070 2,706 7, ,085 81, ,627 5,166 3, ,612 87, ,806 4,606 7, ,933 99, ,766 5,248 9, , , ,175 7,465 10, , , ,291 7,458 14, , , ,116 6,582 17, , , ,462 7,801 13, , , ,570 17,186 15, , , ,414 15,257 16, , , ,202 12,767 15, , , ,910 11,638 29, , , ,109 15,142 33, , , ,110 22,044 54, , , ,144 17,123 75, , , ,254 17, , , , ,982 17, , , , ,967 22, , , , ,993 17, , , , ,400 19, , , , ,847 20, , , , ,297 22, , , , ,289 20, , , , ,502 19, , , , ,727 23, , , , ,044 20, , , , ,172 21, , , , ,293 23, ,400 2,570 80, , ,867 30, ,023 2,636 98, , ,050 22, ,847 2,838 83, , ,057 27, ,688 2, , , ,004 26, ,762 3, , , ,831 26, ,283 3, , , ,522 24, ,983 3,716 98, , ,627 24, ,872 3, , , ,694 24, ,423 3, , , ,036 30, ,899 2, , , ,514 27, ,199 2,508 66, , ,000 23, ,234 2,607 69, , ,071 26, ,554 2,854 76, , ,675 22, ,409 2,903 76, , ,202 23, ,081 3, , , ,989 20, ,429 3,611 96, , ,757 36, ,247 3,802 83, , ,741 34, ,565 3, , , ,492 21, ,141 29,435 63, ,022 Note: data for 2013 are preliminary. 30